It is well known that there is a need for a practical oil/water separator that can cleanse oil spills that occur in bodies of water, such as the oceans, rivers, lakes, and streams. While there are different fluid separation techniques, all of these have drawbacks which render them inadequate to meet present day needs.
One such system, for example, is exemplified in U.S. Pat. No. 3,742,095 granted to Mensing et al on Jul. 3, 1973 entitled "Vortex Flow System " for Separating Oil from an Oil-Water Mixture and commonly assigned to United Technologies Corporation, is a system and apparatus that was intended to cleanse the seas by employing an improved vortex separator. Other systems have been contemplated that centrifuge the fluid in a rotating drum causing the denser liquid to centrifuge to gravitate to the periphery of the rotating drum where it can be collected by a stationary pitot tube immersed in the fluid. The pitot tube, however, creates fluid turbulence which limits the water purity attainable with this concept. This turbulence also increases power consumption, a critical consideration in space-based applications where available power is limited.
Other separation techniques do not rely on centrifugation of the fluid mixture to achieve separation. One such method includes burning the oil once it has been contained. Typically, containment is by use of floating booms that are positioned into place by the use of a vessel. Problems with this approach are that the oil is not recovered, air pollution is generated by the burning process, and the oil is not completely consumed by the burning, hence, the cleanup is incomplete.
Another method utilizes skimmers which pick up oil along with the water from the water surface. The skimming may be by vacuum pumps which pump the oil/water mixture in to a compartment in the hull of a ship. Another approach would be to force the mixture into a compartment by the use of belt skimmer. In either case, the primary mechanism for separation is gravity, i.e. oil which is less dense than water rises to the top of the compartment. Obviously, in addition to the fact that this process is slow, it also has the disadvantage that it requires many more trips to carry the oil/water mixture to off shore containers where the oil is allowed to settle at the top, than it would otherwise require if complete separation were achieved at sea. This is so because if complete separation were achieved at sea, the water could be pumped overboard and the entire compartment would be available for oil storage. Furthermore, separation efficiency by gravity is not nearly as good as with centrifugal separation, since with the latter, several thousand times the gravitational acceleration can be achieved by the rotation of the fluid mixture.
I have found that I can obviate the problems enumerated in the above paragraphs and in accordance with this invention I provide a practical and efficacious centrifugal fluid separator that can be utilized to clean up marine oil spills. It is contemplated that this invention can be utilized to separate the components of any fluid mixture when the components are of different densities.
As one skilled in this art will appreciate the concept of this invention is particularly suited for separating oil from an oil/water mixture however, it affords a multitude of applications for fluid component separation and hence it is not limited in use for oil/water separation. For example, as will become evident from the description to follow, the same basic concept, with some minor modifications, could be used for separation of gas from liquid/gas mixtures, which is a critical process in spacecraft life support systems. Likewise, depending on whether high output flow or high pressure rise is desired slightly different configuration of certain components may be utilized to meet these needs. It will become readily apparent that the description of the preferred embodiment of the water/oil separator will provide a basis for understanding how the invention can be applied for use in other environments, since the same basic principles of operation apply in all cases.